Ask them to do a chest XRay.
I had pneumonia in both my lungs two weeks ago, am just starting to feel better in fact. It started with a cough that my DD gave me and got worse and worse. I couldn't talk without hacking. My throat felt "rattly" when I breathed. Seen at the doctor's (by someone other than my own doctor, who was later a bit peeved) but told I had a virus, no CXR done, no antibiotics. Meanwhile, a PET scan was read that I'd had done 6 days
before I'd been seen at the doctor's, and it showed a pneumonia in my right lower lobe. I started on antibiotics then, but got worse. Felt like I was going to pass out just taking a shower, my heart was racing and I was very winded. Went back to the doctor's, on admission my heart rate was 152 and a chest XRay done then showed it had progressed from one lung to both. Took a while to recover, was placed on bedrest and told to force fluids, and not to even talk!!
The funny part was though, I didn't really feel "sick", just this annoying cough, then weak from the racing heart and I presume decreased oxygenation. I never really knew what walking pneumonia was even though my GF died of it. Now I do.
Good luck, hope you feel better soon.